It was in existence from 1946 to 1952 and its member schools were affiliated with the Wisconsin Interscholastic Athletic Association and the Illinois High School Association.
The SWANI Conference was formed in 1946 by a group of eight similarly-sized high schools: five in Wisconsin (Burlington, Delavan, Elkhorn, Lake Geneva and Whitewater) and three in Illinois (Harvard, Marengo and McHenry).
The five Wisconsin high schools formerly comprised the Southern Five Conference, two high schools in Illinois (Harvard and Marengo) formerly competed in the North Six Conference, and McHenry competed independent of conference affiliation.
[1] This cross-border loop lasted for six seasons before it was dissolved in 1952.
The five Wisconsin high schools competed together for a single season before joining with East Troy, Mukwonago and Wilmot (all formerly of the Southeastern Wisconsin Conference) to form the new Southern Lakes Conference,[2] while the three Illinois high schools joined the IHSA-affiliated SHARK Conference.